Evaluating the role of local and landscape factors on the resilience of mixed-species forest ecosystems under climate uncertainty

评估气候不确定性下当地和景观因素对混合物种森林生态系统恢复力的作用

• 批准号: RGPIN-2016-06438
• 负责人: Elkin, Che
• 金额: $ 2.04万
• 依托单位: University of Northern British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=616309
• 关键词: Evaluating; role; local; landscape; factors

In boreal and sub-boreal mixed-species forests, interactions between coniferous and deciduous trees entail competition for limiting resources, such as light, water and nutrients. However, under some conditions the presence of multiple species is hypothesized to facilitate tree growth. My research aims to improve our understanding of the conditions under which competition or facilitation will occur, and what the concomitant impacts on long-term forest dynamics, the resilience of forests to disturbances, and the provision of forest ecosystem services, such as timber production, carbon storage and biodiversity will be. In particular, I will focus on testing how interactions between species are projected to change under novel future climate conditions. My students and I will examine how forest composition and structure impacts the availability of resources essential for tree growth. By evaluating how resource availability changes within and between years, we will gain insights into where and when competition for resources will be most important, and how projected changes in climate will alter the prevalence of competition or facilitation. Tree and forest development is expected to be influenced not only by the current growth environment, but also by past environmental conditions. We will test for differences in the sensitivity of conifers and deciduous species to past environmental conditions to improve our understanding of how current growth conditions will influence the vulnerability of forests to disturbances and climate-dependent stress, such as drought. Specifically, we will test the hypothesis that under some conditions, mixed-species forest will be more resilient to environmental change and extreme weather events. The long-term dynamics of mixed-species forests are hypothesized to be driven by the interplay of landscape disturbances, environmental conditions including climate, and the developmental state of the forest at the time of disturbance. However, climate change will likely alter the relative competitive ability of species, and the prevalence and intensity of different disturbance types. Therefore, large uncertainty remains regarding how the relative importance of each of these factors, and their interactions, will change under future climate conditions. Using process-based forest models we will examine the mechanisms that drive mixed-species forest dynamics, and project how these processes will change in the future. We will also test how the timing and intensity of different forest management practices influences the dynamics of mixed-species forests at stand and landscape scales. Specifically we will evaluate if forest management can increase the resilience of forests to climate changes, and test how to most effectively trade-off short- and long-term management goals to maintain a diversity of forest ecosystem services under future climate uncertainty.

在北方和亚北方混交林中，针叶树和落叶树之间的相互作用导致了对有限资源（如光、水和养分）的竞争。然而，在某些条件下，假设多种物种的存在有助于树木的生长。我的研究旨在提高我们对竞争或促进将发生的条件的理解，以及对长期森林动态的伴随影响，森林对干扰的恢复力，以及森林生态系统服务的提供，如木材生产，碳储存和生物多样性。特别是，我将专注于测试物种之间的相互作用如何在新的未来气候条件下预测变化。